The present invention relates generally to the field of art concerned with an apparatus and method for the counting of objects and more particularly pertains to the counting of fruits and other objects which are randomly continuously passed through a counting area.
Heretofore, it has been generally known in the fruit packing industry to provide a variety of counting machines for oranges, grapefruit and the like in which the fruit is moved by a conveyor through grading, sizing and counting mechanisms prior to packing or boxing for shipment. Improvements on these machines then followed, as exemplified by U.S. Pat. No. 3,500,982, in which fruit is diverted from a conveyor into a counting machine and into a single-file arrangement in three parallel lanes each of which is provided with a fruit switch actuated arm arranged to be tripped by a fruit as it is discharged from the lane. The fruit in the lanes is discharged therefrom at staggered time intervals and a timing cam is provided to successively briefly close a circuit to a counter through each of the fruit switches at similar staggered time intervals and thereby attain a count for each fruit that is discharged from the machine.
From a consideration of the above noted conventional counting machines in the fruit packing industry, it became evident that there was an existing need for a reliable and dependable but simplified machine which could be utilized for rapidly and accurately electronically counting the objects or fruit, without the necessity of having to utilize mechanically actuated switches or other means which were operable by engaging the fruit. A survey of electronic type counters indicated that such counters, as exemplified by the prior art patents previously listed above, had been developed for the counting of fine particles such as might be found in dust clouds, and the like, as disclosed in U.S. Pat. No. 2,948,469; for the counting of objects such as parcels as disclosed in U.S. Pat. No. 3,692,980; particle detection apparatus for determining the number and size of particles present in a plurality of particles dispersed over a field, as disclosed in U.S. Pat. No. 3,867,613; and apparatus as used in biomedical fields for determining the number of discrete objects in an assemblage, as disclosed in U.S. Pat. No. 3,869,083. The counting techniques in these patents were generally broadly similar in that line-by-line scanning light means were utilized to scan the field containing the parcels or particles, and by suitable sensing means and logic circuitry to provide a count of the objects. Although these patents are suggestive of electronic counting apparatus and methods which might possibly be modified or used to count fruit, such adaptations do not appear to have been made in available counting apparatus for the fruit industry.
According to the present invention, the objects or fruits to be counted are randomly continuously moved through an illuminated counting area, an optical image of the area and illuminated fruit being optically applied to a photodiode self-scanned array which generates a series of analog signals representative of the light levels collected from the associated divisional areas of the image of the counting area. A peak signal detector stores the maximum value video voltage signal. A percentage scaling network is used to generate a voltage which is approximately 60% of the peak value, which is compared to the video signal in order to determine the presence or absence of a fruit in the counting area. By such comparison, the circuitry is designed to produce digital logic binary signal pulses having digital logic values of "1" and "0". These binary signals for a previous scan of the photodiode array are stored, and certain of these stored values are combined with certain present scan binary signals in a recognition pattern which occurs once for each fruit or object which passes through the counting area. When such pattern occurs and is decoded, a count output signal is generated for each fruit or object passing through the counting area.